Mounting means for bearings for sewing machines



Oct. 17, 1967 I.A.LESUE MOUNTING MEANS FOR BEARINGS FOR SEWING MACHINES Filed Sept. 1, 1965 240 22b 22a 24b /7 A9 1 26 /5 H 2 /6 I ,32 5

'i 2028a b O 29 28 5 Sheets-Sheet 1 Inventor IVAN A. LESL/E,deceased, BY CATHERINE M. LESL/E,Executnx,

A Home y Oct. 17, 1967 A. LESLIE 3,347,196

MOUNTING MEANS FOR BEARINGS FOR SEWING MACHINES Filed Sept. 1, 1965 3 Sheets-Sheet 2 L.. .I @-4 flgi lnvenlor IVAN A. LESLIE, deceased, CATHERINE M. LESLIE, Execufrix, BY I Attorney 1. A. LESLIE 3,347,196

MOUNTING MEANS FOR BEARINGS FOR SEWING MACHINES Oct. 17, 1967 5 Sheets-Sheet 5 Filed Sept. 1, 1965 5:5: EEG

Inventor m w w m w m m E, /IA m L um EL am 5 N m Mm 7 Wm United States Patent Ofiice 3,347,196 Patented Oct. 17, 1967 3,347,196 MOUNTING MEANS FOR BEARINGS FOR SEWING MACHINES Ivan Alexander Leslie, deceased, late of Nantwich, England, by Catherine M. Leslie, executrix, Hereford, England, assignor to The Singer Company, Elizabethport, N.J., a corporation of New Jersey Filed Sept. 1, 1965, Ser. No. 484,477 Claims priority, application Great Britain, Sept. 2, 1964, 35,835/64 1 Claim. (Cl. 112-458) ABSTRACT OF THE DISCLOSURE A plate having two holes precisely spaced and surrounded by hemispherically-shaped concavities is removably mounted vertically in the standard of a sewing machine to support the standard ends of the two drive shafts by spherical self-aligning bearings mounted in the hemispherically-shaped concavities in the plate. The spherical self-aligning bearings are covered by hemispherically-shaped caps.

This invention relates to sewing machines of that kind having a lower drive shaft disposed in a base portion of the machine and arranged to drive mechanism in said base portion, and an upper drive shaft disposed in an upper portion of the machine and arranged to drive needle-actuating mechanism.

In the construction of a sewing machine, a basic critical requirement is to achieve consistent, proper timing between a thread-carrying endwise reciprocating needle and an opposed loop-seizing beak of a loop taker. The foregoing requirement must be achieved or else the machine will not sew. In a typical sewing machine, the needle'is reciprocated by a crank at the end of a shaft extending longitudinally through the overhanging upper portion of the machine and the loop taker with the opposed loop-seizing beak is rotated by a shaft extending longitudinally through the base portion of the machine. Since power is applied to only one of the shafts, the shafts must be connected so that they will .rotate in unison and achieve proper timing. The most common way to connect the shafts is by a lug-type timing belt which is looped tautly around sprocket wheels affixed to the standard-end extremities of the shafts. In order toachieve proper timing, the timing belt must have and retain a precise amount of tension when it is mounted on the sprocket wheels, and this tension must be consistent from machine to machine or else each belt would have to be laboriously fitted by hand. Since it is possible to manufacture timing belts of uniform quality, the major variable in the achievement of uniform tension in the timing belts is the distance between the centers of the shafts. Inorder to obtain uniform distances between the centers of the shafts, if an expensive multioperation machine tool is not specially built as for handling large volume production, each casting for a machine frame must be laboriously set up in a drilling machine fitted with a specially-made drilling jig. Either way, the foregoing operation is among the most expensive and time-consuming problems which are encountered in the manufacture of a sewing machine. One

error, and the entire casting for a sewing machine frame can be ruined.

It is, therefore, an object of this invention to provide an improved mounting means for bearings for sewing machines.

Another object of the invention is to provide a mounting means for bearings which includes a plate on which a bearing for the standard-end of the bed shaft and/ or a bearing for the standard-end of the arm shaft are subassembled for subsequent assembly in the standard of the sewing machine.

Another object of the invention is to provide a means for adjusting the lateral distance between the centers of a pair of bearings.

Another object of the invention is to provide an improved self-aligning bearing for a sewing machine.

The present invention provides for the mounting of at least one of the standard-end bearings for the upper and lower drive shafts of a sewing machine on a plate, which may in some cases be position adjustable, and which is subsequently mounted in the standard. It is easier, and much less expensive, to obtain consistently the correct distance between the centers of these bearings by either of the arrangements described with reference to FIGS. 1 and 2 or FIGS. 3, 4 and 5 than it would be with the conventional arrangement in which bearing supports are cast into the machine frame during the casting of the frame. Both modifications of the invention provide an extremely efficient way to consistently obtain the correct distances between the centers of spaced bearings. The plates can be set up in a drilling machine much more easily than a casting for a sewing machine frame. The use of self-aligning bearings further reduces the precision required in drilling the holes for the shafts. It can be appreciated that if self-aligning bearings were not used, the holes for the standard-end and sewing head end bearings would have to be in complete alignment to prevent binding.

According to the invention there is provided a mounting means for bearings for a sewing machine having a frame including a base portion, a standard at one end of the base portion, and upper portion at the top of the standard and overhanging the base portion, and a sewing head at the free end of the upper portion; a mechanism in the base portion; a needle-actuating mechanism in the sewing head; a lower drive shaft in the base portion connected to the mechanism in the base portion; an upper drive shaft in the upper portion connected to the needle-actuating mechanism; bearings for the drive shafts; and connecting means between the drive shafts; said mounting means for bearings comprising a plate having at least one opening formed in said plate for a drive shaft, means for mounting one of the bearings at the opening in the plate, and means for removably mounting the plate in the frame so that the hearing at the opening in the plate supports the extremity of one of the drive shafts.

Preferably the plate has means for adjusting the location of the bearing laterally relative to the opening.

Embodiments of the present invention will now be described, with reference to the accompanying drawings, in which: 7

FIG. '1 is a front elevational view in vertical section of a sewing machine according to the present invention,

FIG. 2 is a cross sectional view taken substantially along the line 22 in FIG. 1,

FIG. 3 is a front elevational view in vertical section and to a larger scale of the standard-end of another sewing machine with parts removed for clearness, illustrating a different bearing arrangement,

FIG. 4 is a sectional enlarged view of a detail along the line 44 in FIG. 3, and

FIG. 5 is a sectional view along the line 5-5 in FIG. 4.

Referring to FIGS. 1 and 2, a sewing machine has a frame in the form of a one-piece cast metal shell having a horizontally extending base portion 11 and a horizontally-extending upper portion 12 which overhangs the base portion 11 and is connected thereto at its rear end by a standard 13. The base portion 11 of the frame contains at its front end loop-forming and workfeed mechanism, indicated generally by the reference numeral 14, driven by a rearwardly-extending drive shaft 15 which is disposed in saidbase portion and constitutes a lower drive shaft of the machine. The overhanging upper portion 12 of the frame has at its front end a head 16 containing needle-actuating mechanism indicated generally by the reference numeral 17 driven by a rearwardly-extending drive shaft 18 which is disposed in said upper portion and constitutes an upper drive shaft of the machine, the two shafts 15, 18 being connected by a belt 19 at their rear ends and being driven by a motor 20. The upper drive shaft 18 is mounted in place by means of two self-aligning bearing devices disposed one at the front end, and one at the rear end; of said shaft 18. Each bearing device consisting of a spherical bearing 21 having a cylindrical inner peripheral surface forming a journal surface rotatably engaged by the shaft 18, and a hemispherically-curved outer surface engaging a hemispherically-eurved concavity or cup 22 or 24 and a hemispherically-shaped cap 22b or 24b, respectively, connected to the plate by fastening means such as screws the cup 22 for the front collar being cast in a vertical interior partition 23 in the upper portion of the housing, and the cup 24 for the rear collar being cast or pressed in the upper part of an upstanding interior separately-formed plate or member 25 secured to the housing such as by screws 26. The two cups 22, 24- face in opposite directions and have circular openings 22a and 24a, respectively, for the upper drive shaft 18.

The lower drive shaft 15 is mounted in place at its such as screws. The lower drive shaft 15 is mounted in place at its front end by a self-aligning bearing device having a box-like housing 29 which is provided with bearings 30 for the drive shaft, and which has opposite side walls 31, 32 secured to side walls 33, 34 of the base portion of the frame of the machine by resilient connections, whereby said box-like housing 29 is resiliently mounted between said housing walls 33, 34 to permit it to move laterally and up and down to suit the desired alignment of the shaft. The resilient connections comprise rubber sleeves 35 which are fitted over metal cores, 36 secured to the housing walls and the outer peripheral surfaces of which engage into laterally presented cylindrical cups 37 on the box-like body part 29, said laterally-presented cups 37 being coaxial with the respective sleeves and cores 35, 36.

In this embodiment, the box-like housing 29 of the front bearing device for the lower shaft also serves as a casing for the feed mechanism, and a hook of the loopforming mechanism is mounted on a free front end of the lower shaft 15, forwards of the box-like housing.

In one modification of the above described embodiment, the bearing devices for the two shafts all consist of spherical bearings having spherically-curved surfaces engaging spherically-curved cups, and in another modification the bearing devices for the two shafts all consist of resiliently-mounted parts.

Referring now to FIGS. 3, 4 and S, the bearing arrangement shown in these drawings differs basicallyv from the FIGS. 1 and 2 arrangement in that the standardend bearings 38, 39 are mounted separately from one another, the upper bearing 38 being mounted on a protrusion 40 formed on or attached to the inner surface of the frame 10, and the lower bearing being in the form of a spherical bearing 39 having a cylindrical innerperipheral surface forming a journal surface rotatably engaged by the lower shaft 15 and a spherically-curved outer surface engaging a spherically-curved cup 42 comprising two complementary hemispherically-shaped caps 45 bolted together by elongated fastening means in the forms of bolts 43 and nuts 44. This lower bearing is supported by the caps 45 in a horseshoe-shaped opening 46a, shown in FIG. 4, in an angled plate 46 by the bolts 43 and nuts 44, the bolts 43 passing through curved slots 47 in the angled plate 46 providing means to adjust the position of the axis of the lower bearing 39 relative to the axis of the upper bearing 32, angled plate 46 being attached by screws 48 to the bed 49 of the sewing machine. The distance between the centers of the shafts 5 and 18 is changed by momentarily loosening the nuts 44 and then shifting the bolts 43 laterally in the slots 47 to shift the bearing 39 laterally.

An adjustable belt-tensioning pulley 50 is provided to maintain tension in the drive-transmitting belt 19 between the lower end upper shafts 15, 18.

Although the invention has been described in its preferred form with a certain degree of particularity, itis understood that the present disclosure of the preferred form has been made by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention.

Having thus set forth the nature of the invention, what is claimed herein is:

A mounting means for bearings for a sewing machine having a frame including a base portion, a standard at one end of the base portion, an upper portion at the top of the standard overhanging the base portion and a sewing head at the free end of the upper portion, a needleactuating mechanism in the sewing head, a substantially horizontal upper drive shaft in the upper portion oftheframe connected to the needle-actuating mechanism, a complementary stitch-forming mechanism in the bed portion, and a lower drive shaft in the bed portion substantially parallel to the upper drive shaft and connected to the complementary stitch-forming mechanism, said mount-v in the standard with the uppermost spherical self-aligning bearing supporting the standard end of the upper drive shaft and the lowermost spherical self-aligning bearingv supporting the standard end of the lower drive shaft.

(References on following page) hemispherically-shaped concavities- 6 References Cited 3,113,809 12/1963 Eggmann 308-26 3,220,676 11/1965 Butts 24815 UNITED STATES PATENTS 3,223,374 12/1965 Butler et a1 24815 X 8/1918 Bergman 30858 X 12/1920 Lippert-Bruenauer 30s 29 5 FOREIGN PATENTS 8/1921 Bartholomew et a1. 308-61 157,097 6/1954 Australia. 2/1927 Dean et a1. 30858 X 11/ 1938 Wood 308-26 JORDAN FRANKLIN, Primary Examiner.

8/1943 Zeier 112--258 10 1950 Hohmann 112 25 10 G. KRIZMANICH, Assistant Examiner. 

